Local cable companies here are great for home users, but they often get picked up by businesses too and it's a huge mistake. They also offer business level service, at MUCH higher costs, but they offer static adressing, company domains and they provide a guaranteed level of service and uptime, not available to home users.
I wouldn't recommend using a local cable provider as a business ISP though, not reliable and not secure enough.
If you bring in your cable/DSL connection you can ruin wireless throughout your organization.
As for satellite, I have a business connection myself, in BC. But if I had to pay for it, it would be close to $600.00 + per month with the bandwidth I use.
Sure there are cheaper sat services, but they don't come remotely close to the service level and reliability I have. Again, this is in the BC region.
The main issues I've had with wireles/ssat in business is connectivity, then bandwidth loss as it generally loses about 7-10% through routing.
I would suggest looking at your ISP's more than anything, reliability, downtime, Quality Of Service (QOS) options, additional bandwidth useage costs (if they say unlimited, you are usually not discussing business level service)they generally give a set limit permonth and offer either a sliding scale or an expensive overage charge.
CHECK the cable provider, I've seen more than my fair share of companies jump on the cable bandwagon only to find out it is not business level quality, and there are huge limitaions.
In most cases you will need to run your own web server and host your own site, thus disqualifying you from residential rate plans, or else they won't offer you your own domain name hosting, and wil charge you for business service.
Weigh the options properly with the providers, explaining clearly that it is for business and a VPN with 3 locations.
You will not find the best value for money or the best option for your company by asking for general technology help, look for local info from the providers.
Good luck, don't forget to weigh ISDN and DSL options, again business class only, if the provider can't offer it, or says it's all the same, go elsewhere..
It WILL work, the issue shouldn't be focused on the best internal connections as much as it should be placed on the better ISP, the better service and security level and above all else, the right price, business class service can be DAMN pricey!